Can a high fever cause a seizure?

A fever-related seizure may involve stiffening, rhythmic jerking, staring, or a brief loss of awareness. The person may be sleepy or confused afterwards. Fever does not prove that the seizure is harmless: infection, low blood sugar, medication or alcohol withdrawal, and inflammation around the brain can also be involved. Meningitis needs urgent consideration when fever occurs with a severe headache, neck stiffness, light sensitivity, a rash, or marked drowsiness. A first seizure, a seizure in an adult, or an event without a known fever should be assessed promptly.

Lay the person on their side on the floor, move hard or sharp objects away, cushion the head, and loosen tight clothing around the neck. Time the movements and stay nearby. Do not restrain them, put anything in their mouth, offer food or drink, or try to lower the temperature with cold water while they are convulsing. When the movements stop, check breathing and remain with them until they are alert. Note what happened and any fever reading for the clinician.

Call emergency services if the seizure lasts more than a few minutes, repeats without recovery, causes an injury, happens in water, or the person has trouble breathing. Seek emergency help for a stiff neck, severe headache, unusual rash, persistent confusion, weakness on one side, or difficulty waking. A child with a first fever-associated seizure should receive medical advice promptly even after recovery. Do not drive if the person remains confused or unwell.

Ask what may have caused the fever, whether examination or tests are needed, how to manage fever safely, and what signs would make another seizure an emergency. Tell the doctor about recent illness, medicines, alcohol exposure, diabetes symptoms, and any family history of seizures.